diff --git a/gpgmymail b/gpgmymail
index 1d23a23..c725fbf 100755
--- a/gpgmymail
+++ b/gpgmymail
@@ -82,8 +82,8 @@ def decode_email(message: email.message.Message) -> email.message.Message:
         for part in quopri_decoded_message.walk():
             if not part.is_multipart():
                 if part.get("Content-Transfer-Encoding") == "base64":
-                    b64_str = part.get_payload()
-                    decoded_b64_str = part.get_payload(decode=True)
+                    b64_str = part.get_payload().encode()
+                    decoded_b64_str = part.get_payload(decode=True).encode()
                     decoded_bytes = decoded_bytes.replace(
                         b64_str,
                         decoded_b64_str